No continuity between back of pot and pot shaft / No continuity with pickguard foil

Alexndrix

New member
I've been going crazy for the past few days trying to figure out why my American Std Strat was presenting the following issue upon rewiring it. The whole purpose of it was to try out some new potentiometers called "Dunlop Superpots":

The diagram used is the one for standard strat SSS wiring and I 've done it several times.

The first thing I noticed after I finished was that the guitar was very quiet, as a properly grounded guitar is, except when I touched the knobs or the switch. Touching these metal parts caused buzzing or hum, so I tried reversing the output jack wires and resoldering all grounds to see if this would fix it. The problem only worsened, which led me to conclude that the jack wires were correct in the first place, so I switched them back to normal.

It took me a while to realize that if I touched the knobs and then the bridge, the buzzing would stop. However, the back of the pots themselves had a good reading of continuity with both the bridge and the output jack (There is a wire going from the back of each tone pot to the ground on the back of the volume pot, of course). Then I went ahead and tested the continuity between all of the pots shafts (volume, tone, and tone) and had a good reading. Then I went ahead and tested between the shafts and the five-way switch, and had a good reading. The shafts/switch tested with the bridge/jack, however, had no reading at all. So, then was when I tested for continuity between the pickguard foil and the bridge and found out that they were not connected, either.

I realized that the real issue was that the pickguard foil itself was not connected to the pots themselves, and only to the five way switch. Normally, with any other kind of pots, they would become shielded by the pickguard foil upon screwing them in. However, these Dunlop Superpots don't seem to have contact within the shaft and the back of the pot.

The problem can be summarized by saying even though the back of the potentiometers have continuity with the bridge and jack, the actual pot shaft does not. This means that the pickguard is not connected to the pots themselves, either, which means that the pickguard is not continuous with the bridge or jack.

What can I do in this situation? I searched the whole net but no one even talks about this issue with the Dunlop super pots.

I'm aware that if I were to put some strings on her, I wouldn't notice as the contact by touching the strings actually completely eliminates the issue. (As seen when I touched the bridge and the pot shaft at the same time.) But I would like this guitar to be perfectly wired even without a neck, like my other strats. My other strats, when testing for continuity, do have a good reading even without strings.

Thanks for reading and I hope you can help me out!
 
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Re: No continuity between back of pot and pot shaft / No continuity with pickguard fo

People have been bltching for years about those pots not having continuity to the mounting threads.

You will just have to add a grounding wire from your volume pot to the foil

Do you have the entire pickup cavity shielded?
 
Re: No continuity between back of pot and pot shaft / No continuity with pickguard fo

People have been bltching for years about those pots not having continuity to the mounting threads.

You will just have to add a grounding wire from your volume pot to the foil

Do you have the entire pickup cavity shielded?

The pickguard is shielded like any regular pickguard, but I didn't do any shielding on the guitar itself. So, just a regular wire from the lump where the ground jack and bridge wires are to a foiled part of the guard?
 
Re: No continuity between back of pot and pot shaft / No continuity with pickguard fo

Yes, from the **star grounding point** where everything grounds together, to the foil.

The reason I asked if you had shielded the cavities, is that your pickguard foil would have got grounded by one of the screws to the body foil.

Note here, how both the pickguard and the Jack Plate get grounded to the body foil:

20.jpg

A $10 roll of 2" copper foil from eBay is a really inexpensive way to get the guitar as quiet as it can be.
 
Re: No continuity between back of pot and pot shaft / No continuity with pickguard fo

Yes, from the **star grounding point** where everything grounds together, to the foil.

The reason I asked if you had shielded the cavities, is that your pickguard foil would have got grounded by one of the screws to the body foil.

Note here, how both the pickguard and the Jack Plate get grounded to the body foil:

View attachment 105418

A $10 roll of 2" copper foil from eBay is a really inexpensive way to get the guitar as quiet as it can be.

That guitar looks perfectly shielded and flawless.

Thank you for solving this for me... I cut a small piece of copper tape that I had around and pasted it to the aluminium foil (because it wasn't taking any solder). After that I ran the wire from the volume pot to the piece of copper tape like you said and everything worked fine.
 
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